Preparation of aluminum-tin alloy by electrodeposition in low-temperature molten salt system

AlCl3-NaCl-KCl low-temperature molten salt system with anhydrous SnCl2 was used to study the preparation of Al-Sn alloy by electrodeposition. The morphology and composition of the alloy were analyzed by scanning electron microscopy (SEM), energy dispersive spectroscopy (EDS) and X-ray diffraction (XRD); The corrosion resistance, wear resistance and antifriction of the alloy were tested and analyzed respectively by polarization curve method and wear and friction experiment; The hardnesses of the alloy and the film substrate adhesion were characterized respectively by Vickers hardness tester and automatic scratch tester for coating adhesion. The results showed that when the SnCl2 content in the electrolyte was 0.04-0.08 g, a medium tin-aluminum alloy with tin content of 10%-18% could be prepared. The optimum deposition temperature was 160-200 degrees C, the deposition time was 40-50 min, and the current density was 40-50 mA/cm(2). With the increase of tin content in the coating, its corrosion resistance gradually became worse and the friction and wear resistance showed a trend of increasing first and then decreasing. When the SnCl2 content was 0.06 g, the tin content in the coating was 14 wt%, the friction and wear resistance were the best. With the increase of the deposition temperature, the film substrate adhesion and hardness of the alloy coating showed a trend of increasing first and then decreasing. When the deposition temperature was 200 degrees C, the best adhesion and hardness were obtained.